Yes, Frankie is using both cores. I am passing the flag "production" to all three libraries but not doing any further customization to the underlying VM/engine/webserver.
Slap cluster (http://learnboost.github.com/cluster/) in front of your node.js express server and re-run the tests with both cores. I'd guess the performance will close to double.
I believe I could optimize all three scenarios by configuring the webservers, VMs and so forth. That is not the point here though so I decided to go with out of the box experience.
Also try running apachebench with the keepalive flag. I know it's not realistic, but then again, hello-world benchmarks never are.
Yup, they never are. :) But I will try with the keep alive flag later, thanks. I need to find some time to build something more relevant, put it on EC2 and then benchmark it properly.